Yes, Lweji, but you'd then have a Class Action (or specific group) suing the Agency or Govt. They still wouldn't sue an individual employee. There have been any number of these regarding US Superfund and Toxic Waste sites. There have also been quite a few against the VA for poor care or benefits denials. IIRC 'Agent Orange' benefits were the result of a Class Action suit agains the VA.
It's not to say that suits against the US are 100% refused. The Govt still has to have 'some' valid reason to refuse to allow a case to proceed. It's just that the number of frivolous or just plain 'crazy' lawsuits are really unbelievable. People file because the Govt has 'put radios in their heads', because they are 'sovereign citizens' and lots of other bollocks.
Personally I'd love to see a 'People of the US vs Donald Trump' Class Action lawsuit. But unfortunately you can't sue someone for being a pretentious, pompous, ignorant, egomaniacal narcissist. (Yet)
On other fronts; I don't think that Comey's testimony is going to be truly 'game changing'. I think it will be a very important brick (or two) in the wall being built, but not the one that completes it. TBH, I don't think it will reveal any critical new information on Russia, it will just refute a lot of Trump's assertions about what he did or didn't say or demand. I think if there is any critical information on Russia or any other dirty dealings, that will be done in the closed session later tomorrow afternoon. I don't think the Committee wants any true 'bombshells' set off in public. They're going to want those set off quietly, where they can contain damage and/or choose what should remain out of the public realm.
It starts at 7am where I live. I'll be watching. DH is going camping which is all to the good as he gets so frustrated and shouts at the TV. At least I'll be able to hear what's being said all the time. lol.
AND, I think the arrest of Reality Winner for leaking info is more about a whistleblower wanting to get information 'out there' so the people knew about it than it is about 'espionage'. I wouldn't be surprised if it comes out that she had been trying to call attention to the information up her 'chain of command' and was shushed because it was damaging to 'certain people' so she just thought 'fuck it' and passed it on. Not saying that's right. But potential whistleblowers are often punished or shushed (in violation of whistleblower statutes) when what they know is damaging to 'certain people'.